Dental crown and bridge removing adaptor

ABSTRACT

A dental crown and bridge removing adaptor is provided with screw tightened arcuate jaw members having crown or bridge gripping faces for securely fastening to a crown or bridge to be removed and an engaging loop for application of removing force by a tapping tool or other force applying means to lift the crown or bridge without injury thereto.

United States Patent Curtis DENTAL CROWN AND BRIDGE Maranda ..32/43 X 1Sept. 12, 1972 4/l930 Flagstad et al ..32/63 Primary Examiner-RobertPeshock AttorneyPaul A. Rose [5 7] ABSTRACT A dental crown and bridgeremoving adaptor is provided with screw tightened arcuate jaw membershaving crown or bridge gripping faces for securely fastening to a crownor bridge to be removed and an engaging loop for application of removingforce by a tapping tool or other force applying means to lift the crownor bridge without injury thereto.

5 Claims, 4 Drawing Figures PATENIEB SE? 12 nan [NY 'EX TOR.

Lyda Dar/el/ Curt/s W4 fl s DENTAL CROWN AND BRIDGE REMOVING ADAPTORDISCUSSION OF PRIOR ART Various tools have been proposed for removal ofdental crowns .or bridges some of which included clamping means forgripping the crown and lifting means such as an elevating screwoperating through a hole drilled in the crown and bearing on theunderlying tooth structure. Also in use is a tapping type tool having ahook to engage the edge of a crown and a sliding weight engaging anabutment to apply the removing force. Use of all of these priorproposals usually results in damage to the crown either incidental touse thereof or deliberately through the drilling of holes for use of theinstrument.

OBJECTS OF THE INVENTION The object of the present invention is toprovide a crown or bridge removing adaptor which embodies crown orbridge engaging jaws carried by tong-like arms and including screwoperated tightening means and force applying means so related that thecrown or bridge is firmly gripped without injury and the removal forceis applied in such a way as to lift the crown or bridge in the directionof insertion without injury thereto.

A further object is to provide a screw tightened tonglike clamp havingcrown gripping jaws provided on opposed ends of pivotally connectedarcuate arms adapted to embrace the crown to be removed for securelygripping the sides of the crown without injury and having a forceapplying tool engaging part carried by one of the arms in the centerline of the pivotal connection whereby the applied force of removal actsto increase the grip of the clamp on the crown and further permits theapplication of selected force applying means for the removal of thecrown without injury thereto.

These and other objects and advantages of the invention will be apparentfrom the following specification with reference to the accompanyingdrawing forming a part thereof and in which FIG. 1 is a side elevationof a crown removing adaptor embodying the invention;

FIG. 2 is a perspective view thereof;

FIG. 3 is a fragmentary view of bridge engaging ends on a modified formof the invention; and

FIG. 4 is a sectional view taken along line 4-4 of FIG. 3.

DESCRIPTION OF INVENTION Referring more particularly to FIG. 1 of thedrawings the crown removing adaptor comprises arcuate arm members 4 and5 pivoted together at 6 and terminating at one end in opposed crownengaging jaws 7 and 8. The end of jaw 8 on the arm 5 is contouredconcave as indicated at 9 for centering on the curve of the crown 22. Inuse the adaptor is applied with the arms embracing the crown and withthe jaws applied to engage the same in a bucco-lingual or labia-lingualdirection near the gingiva. The end of the arm 4 opposite the jaw end-The web portion 10 extends beyond the pivot and terminates in aprojecting ear 12 through which is threaded a tightening screw 13 thelower end of which abuts a shoulder 14 formed on the back of the arm 5.The screw 13 is provided with a knurled head 15 for manual turning tooperate the same. When tightened, the screw end bearing'on the shoulder14 rocks the arms 4 and 5 about the pivot 6 to close the jaws 7 and 8 onthe crown to be removed. The upper end of the arm 5 is bifurcated withthe ends flattened and parallel to receive the lower part of the webportion 10 through which the pivot 6 passes to provide a laterally rigidstructural assembly.

The elongated eye 11 in the webportion of arm 4 provides a loop in whichthe hook 16 of a force applying tool 17 (for instance) may be engagedwith the under side of bail portion 11a to give a controlled directionof force application in removing a crown using the adaptor. As will beunderstood, the sliding weight 18 on the tool 17 is manipulated tostrike a blow on the head 19 of the stem portion 20 to transmit therequired lifting force to the adaptor to break the crown loose.

Since teeth vary considerably in contour, the crown removing adaptordoes not always hang at a straight vertical line. The curve of the bailportion. 11a of the loop was carefully developed to give the best angleof pull in5 most positions of attachment so as to be ableto apply theremoving force in the direction of insertion regardless of the hang ofthe adaptor on the crown.

' It will be noted that the ear 12 on the arm 4 extends substantiallyhorizontally beyond the pivot 6 and is centered over the shoulder 14 onthe curved back of the arm 5 so that the entire assembly presents a lowprofile which is important when working within the mouth of a patient.Also itwill be noted that the contour and placement of the eye 11 of theloop portion of the arm 4 is important in order to give a controlleddirection of force in the removal process.

The adaptor, when firmly seated and gripping the crown in abucco-lingual or labio-lingual direction near the gingiva, has theability to exert the force necessary for the removal of the crown in theoptimum direction which is in line with the path of insertion of thecrown. It furthermore permits the removal of the crown with a minimum offorce and without the usual damage which normally results from the useof most of the lifting implements now available.

As will be obvious from the description, the adaptor is applied to thecrown to be removed by backing off on the screw 13 to permit the jaws 7and 8 to opensufficiently to slip over the top of the crown with thearms embracing the same. The screw is then tightened while holding theadaptor in position so that the jaws close on the crown in thebucco-lingual or labio-lingual direction near the gingiva and lock theadaptor rigidly on the crown.

A force applying tool for the removal of the crown is thenengaged withthe loop 10. It is usually necessary and desirable to use a tool such asthat illustrated to deliver repeated hammer blows or taps in thedirection of removal which is coincident with the direction of insertionso as, to, break the crown loose from its seat on the underlying toothwith the minimum of force and thus minimumchance of'damage. The rigidgrip of the adaptor on the crown transmits the force to the crownwithout slippage thus avoiding scarring or tearing of the margin of thecrown which can easily occur with instruments which engage the edge ofthe margin, for instance.

The bridge removing adaptor shown in FIG. 3 and 4 are similar inconstruction to the crown removing adaptor except that the gripping endsof the pivoted arms are tapered to points 21 which fit into theembrasure between two adjacent teeth on a bridge or splint to beremoved.

The adaptors according to the invention are preferably made of stainlesssteel although they could be made of any other material of suitablestrength and rigidity capable of withstanding the forces applied andrepeated sterilization.

I claim:

1. Dental crown or bridge removing adaptor comprising opposed arcuatefirst and second arm members pivotally connected an adapted to embracethe crown or bridge to be removed with the opposed free ends in grippingrelation therewith, the first arm having a loop portion substantiallycentered over the pivotal connection between the arms and an integralend portion extending beyond the loop portion and overlying a portion ofthe second arm, and a tightening screw member threaded through theextended portion of the first arm and engaging the second arm.

2. Dental crown or bridge removing adaptor according to claim 1 whereinthe first arm member is formed with an enlarged web constituting theloop portion, in which the web has a substantially oval opening centeredover the pivotal connection between the arms and in which the webterminates beyond the pivot in the integral end portion through whichthe adjusting screw is threaded.

3. Dental crown or bridge removing adaptor according to claim 1 whereinthe first arm member is formed with an enlarged web constituting theloop portion, in which the web has a substantially oval opening centeredover the pivotal connection between the arms, in which the webterminates beyond the pivot in the integral end portion through whichthe adjusting screw is threaded and in which the second arm is providedwith an abutment on the back thereof in alignment with the tighteningscrew member.

4. Dental crown removing adaptor according to claim 1 wherein one of thefirst and second arm members is formed with a concave jaw end adaptedtogrip a crown in the bucco-lingual or labio-lingual direction.

5. Dental bridge removing adaptor according to claim 1 wherein the firstand second arm members are formed with opposed tapered end portionsadapted to engage the embrasure between the teeth of a splintor bridgeto be removed.

1. Dental crown or bridge removing adaptor comprising opposed arcuatefirst and second arm members pivotally connected an adapted to embracethe crown or bridge to be removed with the opposed free ends in grippingrelation therewiTh, the first arm having a loop portion substantiallycentered over the pivotal connection between the arms and an integralend portion extending beyond the loop portion and overlying a portion ofthe second arm, and a tightening screw member threaded through theextended portion of the first arm and engaging the second arm.
 2. Dentalcrown or bridge removing adaptor according to claim 1 wherein the firstarm member is formed with an enlarged web constituting the loop portion,in which the web has a substantially oval opening centered over thepivotal connection between the arms and in which the web terminatesbeyond the pivot in the integral end portion through which the adjustingscrew is threaded.
 3. Dental crown or bridge removing adaptor accordingto claim 1 wherein the first arm member is formed with an enlarged webconstituting the loop portion, in which the web has a substantially ovalopening centered over the pivotal connection between the arms, in whichthe web terminates beyond the pivot in the integral end portion throughwhich the adjusting screw is threaded and in which the second arm isprovided with an abutment on the back thereof in alignment with thetightening screw member.
 4. Dental crown removing adaptor according toclaim 1 wherein one of the first and second arm members is formed with aconcave jaw end adapted to grip a crown in the bucco-lingual orlabio-lingual direction.
 5. Dental bridge removing adaptor according toclaim 1 wherein the first and second arm members are formed with opposedtapered end portions adapted to engage the embrasure between the teethof a splint or bridge to be removed.